when backing up your media files on your computer, can you do this

[c=BF6900][i]i still have a windows 7 computer and not in the position to upgrade right now...i recently bought a 4TB external hard drive and are going to back up all my media files on my desktop computer to it.....but i want to know is it possible to copy and paste large quantities of media all at once?

like for example, copy 20 media folders with over a thousand pictures files in each, then paste it over to the hard drive, or can you lose files by doing that?

also copy and paste whole directories to the drive? or is that too risky?[/i][/c]